Fix: #49 All fields were being set as non-nullable. Allow nullable fi…

[crunk1]

…elds to be filterable.

[coveralls]

Pull Request Test Coverage Report for Build 174

• 19 of 19 (100.0%) changed or added relevant lines in 2 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.1%) to 95.298%

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Totals
Change from base Build 173:	0.1%
Covered Lines:	304
Relevant Lines:	319

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💛 - Coveralls

[coveralls]

Pull Request Test Coverage Report for Build 174

• 19 of 19 (100.0%) changed or added relevant lines in 2 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.1%) to 95.298%

---

Totals
Change from base Build 173:	0.1%
Covered Lines:	304
Relevant Lines:	319

---

💛 - Coveralls

[coveralls]

Pull Request Test Coverage Report for Build 174

• 19 of 19 (100.0%) changed or added relevant lines in 2 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.1%) to 95.298%

---

Totals
Change from base Build 173:	0.1%
Covered Lines:	304
Relevant Lines:	319

---

💛 - Coveralls

[coveralls]

Pull Request Test Coverage Report for Build 174

• 19 of 19 (100.0%) changed or added relevant lines in 2 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.1%) to 95.298%

---

Totals
Change from base Build 173:	0.1%
Covered Lines:	304
Relevant Lines:	319

---

💛 - Coveralls

[coveralls]

Pull Request Test Coverage Report for Build 175

• 17 of 17 (100.0%) changed or added relevant lines in 2 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.09%) to 95.268%

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Totals
Change from base Build 173:	0.09%
Covered Lines:	302
Relevant Lines:	317

---

💛 - Coveralls