Standardizing boot loader entry format

{configs/releng/efiboot/loader/entries/archiso-x86_64-{cd,usb}.conf,configs/releng/syslinux/archiso_{pxe,sys}.cfg}:
Standardizing the boot loader entry format by switching all entries to the form:
"Arch Linux install medium (<CARCH>[, <PROPERTY>])".
This removes the distinction between "CD" and "USB" when booting in UEFI "el-torito" (as the information is not useful).
Changing some of the syslinux help text as well to reflect this change. This also drops the specific <CARCH> from the
syslinux help text as it is duplicated information.

Closes #24

configs/releng/efiboot/loader/entries/archiso-x86_64-cd.conf

-title   Arch Linux archiso x86_64 UEFI CD
+title   Arch Linux install medium (x86_64, UEFI)
 linux   /EFI/archiso/vmlinuz.efi
 initrd  /EFI/archiso/intel_ucode.img
 initrd  /EFI/archiso/amd_ucode.img

configs/releng/efiboot/loader/entries/archiso-x86_64-usb.conf

-title   Arch Linux archiso x86_64 UEFI USB
+title   Arch Linux install medium (x86_64, UEFI)
 linux   /%INSTALL_DIR%/boot/x86_64/vmlinuz
 initrd  /%INSTALL_DIR%/boot/intel_ucode.img
 initrd  /%INSTALL_DIR%/boot/amd_ucode.img

configs/releng/syslinux/archiso_pxe.cfg

@@ -2,10 +2,10 @@ INCLUDE boot/syslinux/archiso_head.cfg
 
 LABEL arch64_nbd
 TEXT HELP
-Boot the Arch Linux (x86_64) live medium (Using NBD).
+Boot the Arch Linux install medium using NBD.
 It allows you to install Arch Linux or perform system maintenance.
 ENDTEXT
-MENU LABEL Boot Arch Linux (x86_64) (NBD)
+MENU LABEL Arch Linux install medium (x86_64, NBD)
 LINUX boot/x86_64/vmlinuz
 INITRD boot/intel_ucode.img,boot/amd_ucode.img,boot/x86_64/archiso.img
 APPEND archisobasedir=%INSTALL_DIR% archisolabel=%ARCHISO_LABEL% archiso_nbd_srv=${pxeserver}
@@ -13,10 +13,10 @@ SYSAPPEND 3
 
 LABEL arch64_nfs
 TEXT HELP
-Boot the Arch Linux (x86_64) live medium (Using NFS).
+Boot the Arch Linux live medium using NFS.
 It allows you to install Arch Linux or perform system maintenance.
 ENDTEXT
-MENU LABEL Boot Arch Linux (x86_64) (NFS)
+MENU LABEL Arch Linux install medium (x86_64, NFS)
 LINUX boot/x86_64/vmlinuz
 INITRD boot/intel_ucode.img,boot/amd_ucode.img,boot/x86_64/archiso.img
 APPEND archisobasedir=%INSTALL_DIR% archiso_nfs_srv=${pxeserver}:/run/archiso/bootmnt
@@ -24,10 +24,10 @@ SYSAPPEND 3
 
 LABEL arch64_http
 TEXT HELP
-Boot the Arch Linux (x86_64) live medium (Using HTTP).
+Boot the Arch Linux live medium using HTTP.
 It allows you to install Arch Linux or perform system maintenance.
 ENDTEXT
-MENU LABEL Boot Arch Linux (x86_64) (HTTP)
+MENU LABEL Arch Linux install medium (x86_64, HTTP)
 LINUX boot/x86_64/vmlinuz
 INITRD boot/intel_ucode.img,boot/amd_ucode.img,boot/x86_64/archiso.img
 APPEND archisobasedir=%INSTALL_DIR% archiso_http_srv=http://${pxeserver}/

configs/releng/syslinux/archiso_sys.cfg

@@ -2,10 +2,10 @@ INCLUDE boot/syslinux/archiso_head.cfg
 
 LABEL arch64
 TEXT HELP
-Boot the Arch Linux (x86_64) live medium.
+Boot the Arch Linux install medium on BIOS.
 It allows you to install Arch Linux or perform system maintenance.
 ENDTEXT
-MENU LABEL Boot Arch Linux (x86_64)
+MENU LABEL Arch Linux install medium (x86_64, BIOS)
 LINUX boot/x86_64/vmlinuz
 INITRD boot/intel_ucode.img,boot/amd_ucode.img,boot/x86_64/archiso.img
 APPEND archisobasedir=%INSTALL_DIR% archisolabel=%ARCHISO_LABEL%