always build multicall binary

squashed:
	a2c6b27 - build: automatically generate main() files
	c942f0f - remove MULTICALL=1 build from travis
	cb7b35b - make: remove unnecessary shell command
	69bbb31 - update README
	03a3168 - all: move main() into separate file that links against util crate
	8276384 - make: always build multicall binary
	aa4edeb - make: avoid 'rustc --crate-file-name'
Merge pull request #309 from ebfe/build

make: always build multicall binary
Use Less Memory and Fix Text Mode on Windows/UNIX

The following are changes to fix #303:
  1. hashsum pulls 512KB chunks of the file into memory. This ends up taking 1MB with
     a secondary buffer allocated for windows. hashsum is now able to hash files larger
     than the computer's available memory.
  2. Text no longer transforms to UTF-8. This allows hashing to work on binary files
     without specifying text mode. On Windows, it converts a Windows newline '\r\n' to
     the standard newline '\n'.
  3. Set default modes: Windows uses binary by default, all other systems use text.

Gil Cottle <gcottle@redtown.org>
Merge pull request #317 from redcape/fix-mem-and-text-mode

Use Less Memory and Fix Text Mode on Windows/UNIX
resuming work on K-P
working Knuth-Plass implementation