Bump crate version to v0.5.0

New interfaces:
* Add File::symbol_version_table() interface to get the GNU extension symbol versioning table
* Add Symbol.is_undefined() helper to check if a symbol is defined in this object
* Add File::section_data() which opportunistically parses the CompressionHeader if present

Bug fixes:
* Fix StringTable to return a ParseError on index out of bounds instead of panicking
* Fix File::section_data_as_rels to properly parse Rels (not Relas)

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "elf"
-version = "0.4.0"
+version = "0.5.0"
 authors = ["Christopher Cole <[email protected]>"]
 license = "MIT/Apache-2.0"
 repository = "https://github.com/cole14/rust-elf/"