New functions, varargs

This release features a few improvements.

• Added quote and squote functions for quoting strings.
• Addedb32enc and b32dec for Base32 encoding and decoding.
• add now takes varargs: {{ add 1 2 3 }}
• biggest now takes varargs: {{ biggest 5 6 4 }}
• README is updated

Our tests indicate that making functions variadic seems to be backward compatible, but we're only doing a few this release in case there are some use cases we hadn't thought of.

Release 1.1.0

• Added #4: Added contains function. strings.Contains, but with the arguments switched to simplify common pipelines.
• Added Travis-CI testing support